Input device, storage medium, information input method, and electronic apparatus

ABSTRACT

An optical input device has a display screen, a portion of the display screen being shielded from light by an operating member to implement input processing based on a plurality of input modes. The input device includes an input detection unit including a display unit that displays predetermined input information, and a control unit. The input detection unit detects an area and/or brightness of a light-shielded portion formed on the display screen by the operating member by approaching the display unit. The control unit provides display control of the display unit and input control on the basis of the detected area and/or brightness. The control unit compares the detected area and/or brightness with a predetermined threshold value to select a desired input mode from among the plurality of input modes.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority to Japanese Patent ApplicationJP 2007-183596 filed in the Japanese Patent Office on Jul. 12, 2007, theentire contents of which are incorporated herein by reference.

BACKGROUND

The present application relates to an input device suitable for a mobilephone, a digital camera, an information processing apparatus, or thelike having a display screen which is touched to enter information, astorage medium, an information input method, and an electronicapparatus. More specifically, the present invention relates to an inputdevice including a controller which provides display and input control,in which the area and/or brightness of a light-shielded portion of thedisplay screen that is formed by an operating member is detected and thedetected area and/or brightness is compared with a predeterminedthreshold value to select a desired input mode from among a plurality ofinput modes to implement input processing for each stage of operationaccording to a pressing state of the operating member, resulting in animprovement in operability.

Recently, users or operators have loaded various kinds of content intoportable terminal apparatuses such as mobile phones and personal digitalassistants (PDA) for use. Such portable terminal apparatuses areprovided with an input device. The input device generally includes aninput unit such as a keyboard or a JOG dial, and a display unit such asa touch panel.

Recently, optical touch panels employing liquid crystal panel technologyhave been available as touch panels suitable for input devices. Anoptical touch panel includes, on a liquid crystal display surfacethereof, a light-shielding detection surface having a plurality ofoptical sensors (photosensors), and input information is obtained from alight-shielded portion formed by a user's finger.

A planar display device using this type of optical touch panel and animage obtaining method therefore are disclosed in Japanese UnexaminedPatent Application Publication No. 2006-238053 (pages 4 and 5, FIG. 62).The disclosed planar display device includes a calibration unit thatcontrols a control signal for photosensor pixels. In order to specifythe position of a light-shielded portion, a read signal of each of thephotosensor pixels is detected and a control signal for each of thephotosensor pixels is controlled on the basis of the detected readsignal so that the size of the light-shielded portion can be reduced toobtain one area. This structure allows accurate detection of theposition of a light-shielded portion formed by an object.

An optical input device and information input method of the related artwill be described briefly with reference to the drawings. FIGS. 15A and15B are diagrams showing an example structure of an input device 200 ofthe related art. Referring to a block diagram shown in FIG. 15A, theinput device 200 includes a display unit 201, a backlight 202 stackedbelow the display unit 201, a controller 203 that controls the displayunit 201 and the backlight 202, and a storage unit 204.

The display unit 201 includes a plurality of pixels 210 arranged in amatrix. Referring to a schematic diagram shown in FIG. 15B, each of thepixels 210 includes a display color filter 211, an optical sensor 212for detecting a light-shielded portion, a capacitor, and a wiring region213. The pixels 210 emit light of colors in response to a control signalof the controller 203. The pixels 210 further detect a light-shieldedportion and output the detection result to the controller 203.

In a case where the input device 200 having the structure describedabove performs input processing, first, the controller 203 controls thedisplay unit 201 and the backlight 202 to perform display processingusing the color filters 211 according to a display program stored in thestorage unit 204.

An operator views images displayed on the display unit 201, for example,button icons, and touches a desired button icon with their finger. Thedisplay unit 201 detects a light-shielded portion formed by the fingerusing the optical sensors 212, and outputs the detection result to thecontroller 203. The controller 203 performs input processing accordingto the detection result and a program for input operations, which isstored in the storage unit 204. Further, the input device 200sequentially performs difference determination, coordinate setting, andtouch determination.

FIG. 16 is a diagram showing an example of difference determinationperformed by the input device 200. When a finger touches the displayunit 201 shown in FIG. 16, a light-shielded portion 220 is formed at atouched portion of the display unit 201. The controller 203 detects areduction in brightness and determines the light-shielded portion 220 onthe basis of the reduction in brightness. The controller 203 alsodetects brightness levels of all the pixels 210, and determines adifference brightness level X=|Xn−Xave| between an average brightnesslevel Xave of the detected brightness levels of all the pixels 210 and abrightness level Xn of a pixel 210 that is located within thelight-shielded portion 220. The controller 203 further performsdifference determination to compare the difference brightness level Xwith a predetermined threshold value Xth. If the difference brightnesslevel X is greater than the threshold value Xth, the controller 203performs coordinate setting.

In coordinate setting shown in FIG. 17, the controller 203 defines acentroid 221 at the center of the light-shielded portion 220. After thecentroid 221 is defined, the control device 203 starts touchdetermination.

In touch determination shown in FIG. 18, the controller 203 monitorschanges in the difference brightness level X at the centroid 221. Thecontroller 203 observes a relational characteristic of a derivativevalue (dX/dt) of the difference brightness level X with respect to timet shown in FIG. 18, and determines, for example, input processing attime t1 indicating an inflection point of the gradient of thecharacteristic. At time t2 indicating an inflection point at which thegradient disappears, the input processing is terminated. The inputprocessing based on difference determination, coordinate setting, andtouch determination is implemented in the following procedure.

FIG. 19 is a flowchart showing an example of an input process of theinput device 200. Referring to the flowchart shown in FIG. 19, in stepG1, the controller 203 executes difference determination to constantlycompare the difference brightness level X with the threshold value Xth.When the difference brightness level X becomes greater than thethreshold value Xth, the process proceeds to step G2.

In step G2, the controller 203 defines the coordinates of the centroid221 of the light-shielded portion 220. Then, the process proceeds tostep G3. In step G3, the controller 203 executes touch determination.When the gradient of the relational characteristic (see FIG. 18) of thederivative value (dX/dt) of the difference brightness level X withrespect to time t is inflected or changed at the centroid 221, thecontrol unit 203 detects the time t1 at which the inflection starts.After the time t1 is detected, the process proceeds to step G4, in whichthe controller 203 determines and executes input processingcorresponding to a button icon displayed at the centroid 221. If noinflection is detected for the gradient of the derivative value (dX/dt),the process returns to step G2, and coordinate setting is executedagain. After the input processing is executed in step G4, the processreturns to step G1, and the difference determination is resumed.

Alternatively, after input determination is performed, processingsimilar to the processing of step G3 may be executed to detect the timet2 at which the gradient of the characteristic of the derivative value(dX/dt) disappears. In this case, it can be determined that the pressingof the button icon ends at time t2.

SUMMARY

An optical input device of the related art, such as the planar displaydevice disclosed in Japanese Unexamined Patent Application PublicationNo. 2006-238053 (pages 4 and 5, FIG. 62), executes input processing onthe basis of, mainly, information regarding the position (orcoordinates) of the centroid of a finger. Thus, a problem occurs in thatit is difficult to select an input mode in accordance with a pressingstate of the finger, and the operator may feel uncomfortable duringoperation. Another problem is that the application to a scrollingoperation is difficult because no data is stored for detecting movementof the centroid.

It is therefore desirable to provide an input device, a storage medium,an information input method, and an electronic apparatus in which inputprocessing based on a plurality of different input modes can beimplemented according to a pressing state or sliding movement of anoperating member such as a finger.

According to an embodiment, an optical input device has a displayscreen, a portion of the display screen being shielded from light by anoperating member to implement input processing based on a plurality ofinput modes. The input device includes input detection means including adisplay unit configured to display predetermined input information, theinput detection means detecting at least one of an area and brightnessof a light-shielded portion formed on the display screen by theoperating member by approaching the display unit; and control means forproviding display control of the display unit and input control on thebasis of the at least one of an area and brightness detected by theinput detection means. The control means compares the detected at leastone of an area and brightness with a predetermined threshold value toselect a desired input mode from among the plurality of input modes.

In the input device the control means configured to provide display andinput control compares a detected area and/or brightness of alight-shielded portion formed by an operating member with apredetermined threshold value to select a desired input mode from aplurality of input modes. Therefore, input processing can be implementedfor each stage of operation according to a pressing state of theoperating member.

According to another embodiment, a storage medium stores a programadapted to implement input processing based on a plurality of inputmodes according to a light-shielding operation executed by an operatingmember on a display screen on which predetermined input information isdisplayed. The program includes the steps of detecting at least one ofan area and brightness of a light-shielded portion formed on the displayscreen by the operating member by approaching the display screen;comparing the detected at least one of an area and brightness with apredetermined threshold value to select a desired input mode from amongthe plurality of input modes; defining a detection area so as tocorrespond to the input information on the basis of the selected inputmode, the detection area having a shape and size corresponding to theselected input mode; detecting at least one of a position and movementof the light-shielded portion within the detection area; and determininginput processing in the desired input mode on the basis of the detectedat least one of a position and movement.

Therefore, an input device and electronic apparatus having the storagemedium can be reproducibly operated.

According to another embodiment, an information input method forimplementing input processing based on a plurality of input modesaccording to a light-shielding operation performed, using an operatingmember, on predetermined input information displaced on a display screenincludes the steps of detecting at least one of an area and brightnessof a light-shielded portion formed on the display screen by theoperating member by approaching the display screen; comparing thedetected at least one of an area and brightness with a predeterminedthreshold value to select a desired input mode from among the pluralityof input modes: defining a detection area so as to correspond to theinput information on the basis of the selected input mode, the detectionarea having a shape and size corresponding to the selected input mode;detecting at least one of a position and movement of the light-shieldedportion within the detection area; and determining input processing inthe desired input mode on the basis of the detected at least one of aposition and movement.

In the information input method, an area and/or brightness of alight-shielded portion formed by an operating member is detected, and iscompared with a predetermined threshold value to select a desired inputmode from a plurality of input modes. Therefore, input processing can beimplemented for each stage of operation according to a pressing state ofthe operating member.

According to another embodiment, an electronic apparatus includes anoptical input device having a display screen, a portion of the displayscreen being shielded from light by an operating member to implementinput processing based on a plurality of input modes. The input deviceincludes input detection means having a display unit configured todisplay predetermined input information, the input detection meansdetecting at least one of an area and brightness of a light-shieldedportion formed on the display screen by the operating member byapproaching the display unit; and control means for providing displaycontrol of the display unit and input control on the basis of the atleast one of an area and brightness detected by the input detectionmeans. The control means compares the detected at least one of an areaand brightness with a predetermined threshold value to select a desiredinput mode from among the plurality of input modes.

The electronic apparatus includes an input device of an embodiment. Withthis structure, input processing can be implemented for each stage ofoperation according to a pressing state of an operating member.Therefore, input processing can be implemented for each stage ofoperation such as startup, scrolling, or determination according to apressing state of the operating member such as approaching, touching, orpressing.

According to an embodiment, control means for providing display andinput control is provided. An area and/or brightness of a light-shieldedportion formed an operating member is detected, and is compared with apredetermined threshold value to select a desired input mode from aplurality of input modes. With this structure, input processing can beimplemented for each stage of operation according to a pressing state ofthe operating member. Therefore, input processing can be implemented foreach stage of operation such as startup, scrolling, or determinationaccording to a pressing state of an operating member such asapproaching, touching, or pressing. Furthermore, a detection areasuitable for each operation of input processing can be defined for anindividual input mode to implement an easy scrolling operation.Moreover, a tactile sensation which mimics that of a mechanicaloperation button and/or a sound can be given to the operating member.Therefore, the uncomfortable feeling perceived by the operating membercan be reduced, and the operability can be improved.

Additional features and advantages are described herein, and will beapparent from the following Detailed Description and the figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram showing an example structure of an input deviceaccording to a first embodiment;

FIG. 2A is a schematic cross-sectional view showing an example structureof a display screen;

FIG. 2B is a diagram showing an example structure of a pixel of thedisplay screen;

FIGS. 3A to 3D are diagrams showing an example of input processing in aninput mode I;

FIGS. 4A to 4D are diagrams showing an example of input processing in aninput mode II;

FIGS. 5A to 5D are diagrams showing an example of input processing in aninput mode III;

FIGS. 6A to 6D are diagrams showing examples of tactile sensationsprovided in the input mode II;

FIGS. 7A to 7F are diagrams showing examples of tactile sensationsprovided in the input mode III;

FIG. 8 is a table showing an example of conditions for selecting inputmodes;

FIG. 9 is a flowchart showing an example of an input process of theinput device;

FIG. 10 is a table showing an example of conditions for selecting inputmodes according to a second embodiment;

FIG. 11 is a perspective view showing an example structure of a mobilephone according to a third embodiment;

FIG. 12 is a block diagram showing an example internal structure of themobile phone;

FIG. 13 is a perspective view showing an example structure of a videocamera according to a fourth embodiment;

FIG. 14 is a perspective view showing an example structure of a mobilepersonal computer according to a fifth embodiment;

FIGS. 15A and 15B are diagrams showing an example structure of an inputdevice of the related art;

FIG. 16 is a diagram showing difference determination performed by theinput device;

FIG. 17 is a diagram showing an example of coordinate setting performedby the input device;

FIG. 18 is a characteristic diagram showing an example of touchdetermination performed by the input device; and

FIG. 19 is a flowchart showing an example of an input process of theinput device.

DETAILED DESCRIPTION

An input device, a storage medium, an information input method, and anelectronic apparatus according to embodiments will now be described withreference to the drawings.

First Embodiment

FIG. 1 is a diagram showing an example structure of an input device 100according to a first embodiment. The input device 100 shown in FIG. 1 issuitably used for an electronic apparatus such as a mobile phone. Theinput device 100 includes a display screen 11 with built-in opticalsensors, and implements information input based on sliding movement ofan operating member touching the display screen 11. The input device 100performs, instead of an existing input operation using operationbuttons, a screen input operation by causing an operating member toapproach, touch, and press input information displayed on the displayscreen 11, for example, an icon ICx (not shown in FIG. 1).

When a portion of the display screen 11 is shielded from light by anoperating member such as a finger, the input device 100 estimates apressing state of the operating member on the basis of thelight-shielded portion, and implements input processing in acorresponding input mode. In this case, the input device 100 alsoprovides a tactile sensation corresponding to the input operation of theoperating member. The input device 100 includes the display screen 11, acontroller 15, a storage unit 16, and an actuator 20.

The display screen 11 is a liquid crystal screen with built-in opticalsensors, and includes a display unit 10 and a backlight 12. The displayunit 10 includes a plurality of pixels 40 arranged in a matrix. Each ofthe pixels 40 includes a display color filter and an input-detectionoptical sensor. The pixels 40 emit light in response to a control signalD4 of the controller 15, and output brightness information S1 andposition (coordinate) information S2 of the light-shielded portion tothe controller 15.

The controller 15 provides display and input control of the displayscreen 11. The controller 15 that controls the display screen 11 isconnected to the storage unit 16. The storage unit 16 is an example of astorage medium, and stores programs implementing input processing basedon a plurality of input modes. The storage unit 16 stores display dataD4 for providing display on the display screen 11, and controlinformation Dc corresponding to the display data D4, such as theposition of a detection area of the icon ICx and a vibration mode. Thecontrol information Dc includes a program for selecting a desired inputmode from among a plurality of input modes, and threshold data used forselection of an input mode. The storage unit 16 may be an electricallyerasable programmable read-only memory (EEPROM), a ROM, or a randomaccess memory (RAM).

The controller 15 reads the control information Dc from the storage unit16, and compares the detected area and/or brightness of thelight-shielded portion on the display screen 11 with a predeterminedthreshold value to select a desired input mode from among a plurality ofinput modes. The controller 15 estimates a pressing state of theoperating member on the basis of mainly the brightness information S1.

The controller 15 further supplies a vibration control signal Sa to theactuator 20 to generate a vibration mode corresponding to the inputoperation. The actuator 20 may be a micro receiver having an actuatorfunction. The actuator 20 has functions of a receiver (or earpiece) fortelephone calls, a speaker, and an actuator.

The actuator 20 vibrates the display screen 11 according to a vibrationpattern corresponding to the input mode, and gives or presents a tactilesensation to the operating member. In response to an input ofinformation using the display screen 11, the actuator 20 generates aclick sound (cyber-switch operating sound) and gives a tactile sensationto an operator touching the display screen 11. The input device 100 isconfigured in the manner described above. The display screen 11 forinputting information will be described.

FIGS. 2A and 2B are diagrams showing an example structure of the displayscreen 11. The display screen 11 shown in FIG. 2A may be an example ofinput detection means. The display screen 11 includes the display unit10 that displays predetermined input information, and detects the area,brightness, position, etc., of a light-shielded portion formed by anoperating member approaching the display unit 10.

The display screen 11 is formed of a liquid crystal screen with built-inoptical sensors. The display screen 11 includes a display plate 13 whichis touched by an operating member, and an air space 14 provided belowthe display plate 13. Below the air space 14, the display unit 10 andthe backlight 12 are provided. The display plate 13 may be formed of aglass, polymethylmethacrylate (PMMA), or polycarbonate (PC) plate with athickness d of about 0.2 mm to about 1.5 mm. The air space 14 may be anair space with a thickness of about 25 μm to about 0.3 mm. Instead of anair space, a transparent adhesion layer may be formed. The display unit10 includes the plurality of pixels 40. The display unit 10 and thebacklight 12 for liquid crystal display are connected to the controller15.

The display screen 11 is connected to, for example, a housing 30 of amobile phone 1 (see FIG. 11). The mobile phone 1 includes no operationbutton, and is configured such that a finger touches or presses on thedisplay screen 11 to implement information processing such as telephonecalling, email communication, or photographing. A camera 4 is mounted ona rear surface of the display screen 11, and is operated to capture anobject image. The actuator 20 is provided on an upper portion of thehousing 30. A module antenna 6 is mounted inside the housing 30, and acircuit substrate 7 is provided within the housing 30. A battery 5 isaccommodated in the housing 30 to supply power to the circuit substrate7, the display screen 11, and other units.

Referring to a schematic diagram shown in FIG. 2B, each of the pixels 40of the display unit 10 includes a display color filter 41, an opticalsensor 42 for input detection, a capacitor, and a wiring region 43. Eachof the pixels 40 causes the color filter 41 to emit light in response toa control signal D4 of the controller 15, and the optical sensor 42mainly detects the brightness of received light. The display unit 10outputs light-shielding information including brightness information S1and position information S2, which is detected by the optical sensors42, to the controller 15. The display screen 11 is configured in themanner described above.

The input device 100 selects a desired input mode from among a pluralityof input modes according to the light-shielding information from thedisplay screen 11. The input device 100 selects an input mode I when afinger 80, which is an example of an operating member, approaches thedisplay screen 11, selects an input mode II when the finger 80 touchesthe display screen 11, and selects an input mode III when the finger 80presses on the display screen 11. The details of input processing in theinput modes I to III will be described in the context of an addresssearch operation of the mobile phone 1.

FIGS. 3A to 3D are diagrams showing an example of input processing inthe input mode I. When a user who desires to start address search placesthe finger 80 close to the display screen 11 of the input device 100,first, the input mode I is selected. The input mode I is selected when,as shown in a perspective view of FIG. 3A, the finger 80 approaches thedisplay screen 11 so that the distance between the display screen 11 andthe finger 80 becomes substantially equal to a value Δh.

When the finger 80 approaches the display screen 11, a light-shieldedportion 82 is produced by the shadow of the finger 80. Thelight-shielded portion 82 has a brightness level Xn lower than anaverage brightness level Xave of the entire display screen 11. Thecontroller 15 determines the difference brightness level X=|Xn−Xave|between the brightness level Xn and the average brightness level Xave onthe basis of the brightness information S1, and operates to select theinput mode I if the difference brightness level X is within a selectionrange for the input mode I.

If the input mode I is selected, input processing for starting addresssearch is executed. Icons IC1 and IC2 are displayed on the displayscreen 11. The icons IC1 and IC2 indicate input information to beselected. The icon IC1 represents a group number, and the icons IC2represent names of persons included in a group identified by the groupnumber.

In the input mode I, detection areas F1 and F2 are defined at positionscorresponding to those of the icons IC1 and IC2 on the display screen 11so as to have the same shapes and sizes as the icons IC1 and IC2,respectively (see FIG. 3B). That is, the icons IC1 and IC2 and thedetection areas F1 and F2 are formed using the color filters 41 andoptical sensors 42 of identical pixels 40. In the following processingin the input mode I, input detection is performed using the pixels 40 ofthe detection areas F1 and F2.

After the detection areas F1 and F2 are defined, processing based on theposition information S2 is mainly performed. In this processing, thecontroller 15 detects the coordinates of the centroid of thelight-shielded portion 82 on the basis of the position information S2.When the coordinates of the centroid of the light-shielded portion 82are detected, as shown in a perspective view of FIG. 3C, one of theicons IC2 that is located below the finger 80 is displayed in anenlarged manner.

As shown in a table of FIG. 3D, in the input mode I, no sound or tactilesensation is generated in accordance with the input processing. Theinput mode I allows a user to recognize that the mobile phone 1 hasidentified the position of the finger 80 and has started inputprocessing. When the finger 80 further approaches and touches thedisplay screen 11, the input mode II is selected.

FIGS. 4A to 4D are diagrams showing an example of input processing inthe input mode II. The input mode II is selected when, as shown in aperspective view of FIG. 4A, the finger 80 touches the display screen11. The controller 15 operates to select the input mode II if thedifference brightness level X is within a selection range for the inputmode II. If the input mode II is selected, input processing forscrolling is executed.

If the input mode II is selected, detection areas F3 and F4 are definedin edge portions of the icons IC1 and IC2 on the display screen 11 (seeFIG. 4B). When the light-shielded portion 82 moves across the detectionarea F3 or the detection areas F4, as shown in a perspective view ofFIG. 4C, the icons IC2 are scrolled in a movement direction of thefinger 80. In this case, the direction of scrolling, the speed ofscrolling, and the amount of scrolling are determined on the basis ofthe moving direction, moving speed, and moving amount of the centroid ofthe light-shielded portion 82, which are derived from the positioninformation S2.

As shown in a table of FIG. 4D, in the input mode II, a sound and a*tactile sensation are generated in accordance with the scrollingoperation. For example, a small beep sound is generated when the finger80 moving across the display screen 11 passes through the detection areaF4 formed in the edge portion of the icon IC2. A vibration waveform forshape recognition is also generated at the same time. At this time, thefinger 80 perceives a tactile sensation similar to that of tracing alongthe periphery of an operation button. After the icons IC2 indicating thenames of persons to be searched in the input mode II are displayed, theuser presses a desired one of the icons IC2 with the finger 80. Inresponse to the pressing operation by the finger 80, the input mode IIIis selected.

FIGS. 5A to 5D are diagrams showing an example of input processing inthe input mode III. The input mode III is selected when, as shown in aperspective view of FIG. 5A, a pressing operation by the finger 80 isperformed. The controller 15 operates to select the input mode III ifthe difference brightness level X is within a selection range for theinput mode III.

In the input mode III, input processing for determination (or setting)is executed. If the input mode III is selected, detection areas F5 andF6 shown in FIG. 5B are defined in center portions of the icons IC1 andIC2 on the display screen 11.

After the input mode III is set, when the centroid of the light-shieldedportion 82 is detected in any of the detection areas F5 and F6, as shownin a perspective view of FIG. 5C, the color of one of the icons IC2 thathas been pressed by the finger 80 is changed. For example, the color ofan icon area and the color of text are reversed.

As shown in a table of FIG. 5D, a sound and a tactile sensation aregenerated in accordance with the determination operation. In the inputmode III, when the finger 80 presses any of the detection areas F5 andF6 on the display screen 11, for example, a relatively strong sound,e.g., a warning beep sound, is generated and a vibration waveform forproviding a click feeling is also generated. The vibration waveformgives a click feeling to the finger 80, which is similar to the feel ofpressing a tact button, and the sound allows the user to recognize thatdetermination has been entered. A tactile sensation providing functionin the input modes II and III will be described.

FIGS. 6A to 6D are diagrams showing examples of tactile sensationsprovided in the input mode II. FIG. 6A shows a manner in which thefinger 80 traces along the periphery of a mechanical projectingoperation button 83. Referring to FIG. 6A, when the finger 80 moves in adirection indicated by an arrow from a state 80 a, the finger 80 touchesan edge portion of the operation button 83 at a stage 80 b (see FIG.6B). When the finger 80 further moves in the direction indicated by thearrow, the finger 80 slides over an upper surface of the operationbutton 83 at a stage 80 c, and touches the edge portion at a stage 80 d.Then, the finger 80 enters a non-contact state 80 e.

In the input mode II, a vibration waveform shown in FIG. 6C is generatedfrom the actuator 20 to vibrate the display screen 11 when the finger 80passes through any of the detection areas F3 and F4 shown in FIG. 4B inorder to achieve the sensation of touching the operation button 83 shownin FIGS. 6A and 6B. When the finger 80 touching the display screen 11passes through the icon ICx (any of the icons IC1 and IC2), the finger80 perceives a relatively light tactile sensation such as a momentaryvibration as shown in FIG. 6D. Thus, the operator perceives a tactilesensation similar to the sensation of tracing along the periphery of theoperation button 83.

FIGS. 7A to 7F are diagrams showing examples of tactile sensationsprovided in the input mode III. FIG. 7A shows a manner in which thefinger 80 presses a tact switch 84. Referring to FIG. 7A, the finger 80moves in a pressing direction in stages 80 f to 80 i, presses the tactswitch 84 to the bottom in a stage 80 j, and moves in a releasingdirection in stages 80 k to 80 n.

When the finger 80 moves from above in the pressing direction, a clickfeeling obtained when the tact switch 84 is turned on is obtained in thestage 80 h (see FIG. 7B). When the finger 80 moves in the releasingdirection after it presses the tact switch 84 to the bottom, a clickfeeling obtained when the tact switch 84 is turned off is obtained inthe stage 80 l. This is because, as shown in FIG. 7D, a reaction forceof the tact switch 84 is exerted against the pressing force of thefinger 80 shown in FIG. 7C.

In the input mode III, a vibration waveform shown in FIG. 7E isgenerated from the actuator 20 to vibrate the display screen 11 when thefinger 80 presses any of the detection areas F5 and F6 shown in FIG. 5Bin order to achieve the sensation of pressing the tact switch 84 shownin FIG. 7A. When the finger 80 touching the display screen 11 pressesthe icon ICx, a click feeling such as a momentary vibration as shown inFIG. 7F is obtained. Thus, the operator pressing the icon ICx perceivesa tactile sensation similar to the sensation of pressing the tact switch84. In this way, the tactile sensation function in the input modes IIand III is implemented. Selection conditions for identifying the inputmodes I to III will be described.

FIG. 8 is a table showing an example of conditions for selecting inputmodes. In the first embodiment, an input mode is selected by determiningwhether or not the difference brightness level X determined from thebrightness information S1 satisfies a predetermined selection condition.For example, in determination 1, it is determined whether or not thedifference brightness level X satisfies a selection condition of theinput mode I. If the selection condition is satisfied, the input mode Iis selected (see FIG. 9).

In an input mode selection process based on the brightness in thisexample, brightness threshold data D11, D12, and D13 (where D11<D12<D13)are read from the control information Dc stored in the storage unit 16.The threshold data D11 to D13 are determined in advance based on anexperimental result or the like, and are stored in the storage unit 16.

The selection of an input mode is performed on the basis of themagnitude of the difference brightness level X=|Xn−Xave|. The differencebrightness level X is a difference between an average Xave of brightnesslevels detected from all the pixels 40 and a brightness level Xndetected from a pixel in the light-shielded portion 82.

Determination 1 is a determination for the input mode I. Indetermination 1, it is determined whether or not the differencebrightness level X satisfies a selection condition of the input mode I.In the selection condition for determination 1, the differencebrightness level X falls within a range of equal to or more than thethreshold data D11 and less than the threshold data D12. The thresholddata D11 and D12 are set to a minimum value and maximum value of thedifference brightness level X, respectively, which are obtained when thedistance between the finger 80 and the display screen 11 issubstantially equal to the value Δh.

Determination 2 is a determination for the input mode II. Indetermination 2, it is determined whether or not the differencebrightness level X satisfies a selection conditions of the input modeII. In the selection condition for determination 2, the differencebrightness level X falls within a range of equal to or more than thethreshold data D12 and less than the threshold data D13. The thresholddata D12 and D13 are set to a minimum value and maximum value of thedifference brightness level X, respectively, which are obtained when thefinger 80 touches the display screen 11.

Determination 3 is a determination for the input mode III. Indetermination 3, it is determined whether or not the differencebrightness level X satisfies a selection condition of the input modeIII. In the selection condition for determination 3, the differencebrightness level X falls within a range of equal to or more than thethreshold data D13. The threshold data D13 is set to a minimum value ofthe difference brightness level X, which is obtained when the finger 80presses the display screen 11. Accordingly, the determination based onthe selection conditions are executed to select an input mode. Aninformation input method using those selection conditions will bedescribed.

FIG. 9 is a flowchart showing an example of an input process of theinput device 100. In a case where the mobile phone 1 is operated, whenthe finger 80 approaches the display screen 11 on which the icon ICx isdisplayed, first, the controller 15 estimates a pressing state (such asapproaching, touching, or pressing) of the finger 80 to select an inputmode, and executes input processing for each stage of operation.

For example, in the input processing for address search, any of theinput modes I to III described with reference to FIGS. 3A to 5D isselected, and input processing for startup, scrolling, and determinationis executed. Programs and threshold data for these operations of inputprocessing are stored as the control information Dc in the storage unit16.

The controller 15 reads a program and threshold data corresponding to aninput operation of an operating member from the control information Dc,and executes input processing corresponding to an input mode. In step A1shown in the flowchart of FIG. 9, the controller 15 executes differencedetermination using the read program and threshold data as processingconditions, and detects the finger 80 approaching the display screen 11.At this time, the controller 15 calculates the difference brightnesslevel X of the light-shielded portion 82, and determines whether or notthe difference brightness level X is equal to or more than, for example,the threshold data D11. When the difference brightness level X becomesequal to or more than the threshold data D11, it is determined that thefinger 80 has approached the display screen 11. Then, the processproceeds to step A2.

In step A2, determination 1 is executed, and it is determined whether ornot an input mode, which is selected from the approaching state of thefinger 80, is the input mode I. The controller 15 compares thedifference brightness level X with the threshold data D11 and D12 todetermine whether or not the difference brightness level X is equal toor more than the threshold data D11 and is less than the threshold dataD12. When the difference brightness level X is equal to or more than thethreshold data D11 and is less than the threshold data D12, the inputmode I is selected. Then, the process proceeds to step A3. If the inputmode I is not selected, the process proceeds to step A5.

In step A3, the controller 15 defines the detection areas F1 and F2 forthe input mode I at display positions of icons ICx on the display screen11. In this example, the detection areas F1 and F2 are defined so as tooverlap the icons IC1 and IC2, respectively. After the detection areasF1 and F2 are defined, the process proceeds to step A4.

In step A4, the input processing corresponding to the input mode I isexecuted, and a position of the light-shielded portion 82 in any of thedetection areas F1 and F2 is detected. At this time, the controller 15calculates the coordinate information of the centroid of thelight-shielded portion 82 on the basis of the position information S2 todetermine one of the icons ICx that is located below the finger 80, anddisplays this icon ICx in an enlarged manner. The enlarged display ofthe icon ICx allows the operator to recognize the ability of inputoperation using the icon ICx or the start of the input processing.

If the input mode I is not selected and the process proceeds from stepA2 to step A5, determination 2 is executed, and the differencebrightness level X is compared with the threshold data D12 and D13 todetermine whether or not the selection condition of the input mode II issatisfied. That is, it is determined whether or not the finger 80 hastouched the display screen 11. For example, as indicated indetermination 2 shown in FIG. 8, it is determined whether or not thedifference brightness level X is equal to or more than the thresholddata D12 and is less than the threshold data D13. If the input mode IIis determined as a result of the determination, the process proceeds tostep A6. If the input mode II is not determined, the process proceeds tostep A8.

In step A6, detection areas for the input mode II are defined on thedisplay screen 11. For example, the detection areas F3 and F4 aredefined in edge portions of the icons IC1 and 1C2, respectively. Afterthe detection areas F3 and F4 are defined, the process proceeds to stepA7.

In step A7, the input processing for the input mode II is executed. Atthis time, the controller 15 scrolls an icon ICx located below thefinger 80 according to the moving direction, moving speed, and movingamount of the centroid of the light-shielded portion 82, which aredetermined on the basis of the position information S2. In this scrolloperation, the vibration waveform shown in FIG. 6C is generated toprovide a tactile sensation for shape recognition, which is perceivedwhen the operator traces along the periphery of the operation button 83;to the operator. In addition to the tactile sensation, the sound shownin FIG. 4D is generated to give a scroll feeling to the operator, and ascroll speed is also presented.

If the input mode II is not selected and the process proceeds from stepA5 to step A8, determination 3 is executed, and it is determined whetheror not the selection condition of the input mode III is satisfied. Thatis, it is determined whether or not a pressing operation has beenperformed by the finger 80. For example, as indicated in determination 3shown in FIG. 8, the difference brightness level X is compared with thethreshold data D13. If the difference brightness level X is equal to ormore than the threshold data D13, the input mode III is determined.Then, the process proceeds to step A9. If the input mode III is notdetermined in determination 3, the process returns to step A1. If theprocess returns to step A1, the difference determination process startsagain.

In step A9, detection areas for the input mode III are defined on thedisplay screen 11. For example, the detection areas F5 and F6 aredefined at the center portions of the icons IC1 and IC2, respectively.After the detection areas F5 and F6 are defined, the process proceeds tostep A10.

In step A10, input processing for the input mode III is executed. Atthis time, the controller 15 changes the color of an icon ICx pressed bythe finger 80 on the basis of the coordinate information of the centroidof the light-shielded portion 82 specified by the position informationS2, and performs input processing for the determination stage todetermine and enter the input information of the icon ICx. In thepressing operation for the determination, the vibration waveform shownin FIG. 7E is generated by the actuator 20 to give a tactile sensation,which mimics a click feeling of the tact switch 84, to the operator. Inaddition to the tactile sensation, the sound shown in FIG. 5D isgenerated to allow the operator to recognize that the determination hasbeen done. The input process of the input device 100 is executed in themanner described above.

Accordingly, the input device 100 according a first embodiment isconfigured such that the controller 15 that provides display and inputcontrol compares a detected brightness of the light-shielded portion 82formed by the finger 80 with a predetermined threshold value to select adesired input mode from among the three input modes. Therefore, inputprocessing can be implemented for each stage of operation according to apressing state of the finger 80. For example, input processing can beimplemented for a stage of operation such as startup, scrolling, ordetermination according to a pressing state of the finger 80 such asapproaching, touching, or pressing.

Furthermore, a detection area suitable for each operation of inputprocessing can be defined for every input mode, resulting in animprovement in operability. For example, the detection areas F3 and F4for scrolling can be defined in the edge portions of the icons ICx, thusproviding an easy scrolling operation.

Moreover, a tactile sensation or sound which mimics that of a mechanicaloperation button can be given to an operating member. For example, inthe scrolling process, a tactile sensation of tracing along theperiphery of an operation button can be provided using the detectionareas F3 and F4 defined in the edge portions. The uncomfortable feelingperceived by the operating member can therefore be reduced.

In addition, the detection areas F5 and F6 for determination can bedefined at the center portions of icons ICx. Thus, the space betweenadjacent detection areas is increased to prevent erroneous input fordetermination.

Second Embodiment

FIG. 10 is a table showing an example of conditions for selecting inputmodes according to a second embodiment. In the second embodiment, whenthe input device 100 described in the first embodiment executes inputprocessing according to the process shown in the flowchart of FIG. 9,area-based determination rather than brightness-based determination isperformed. In the second embodiment, the controller 15 of the inputdevice 100 determines whether or not the area (or the number pixels) ofthe light-shielded portion 82 satisfies a predetermined selectioncondition to select an input mode.

In this input mode selection, the threshold data D11 and D12 of thedifference brightness level X and threshold data D21 and D22 of an area(where D21<D22) are read from the control information Dc stored in thestorage unit 16. The threshold data D21 and 22 are determined based onan experimental result, statistic result, or the like, and are stored inadvance in the storage unit 16.

The input device 100 detects areas (or the numbers of pixels) N×1 andN×2 of the light-shielded portion 82 on the basis of the brightnessinformation S1 and the position information S2. The area N×1 representsthe number of pixels obtained when the difference brightness level X isequal to or more than the threshold data D11 and is less than thethreshold data D12, and the area N×2 represents the number of pixelsobtained when the difference brightness level X is equal to or more thanthe threshold data D12 (D11<D12). That is, the area N×1 indicates thearea of a shadow of the finger 80 that has not touched the displayscreen 11, and the area N×2 indicates the area of a portion touched bythe finger 80.

Determination 1 is a determination for the input mode I. Indetermination 1, it is determined whether or not a selection conditionof the input mode I is satisfied. In this example, the selectioncondition for determination 1 is that the area N×1 is greater than thethreshold data D21. The threshold data D21 is set so as to match an areaof the shadow of the finger 80, which is obtained when the distancebetween the finger 80, and the display screen 11 becomes substantiallyequal to a value Δh.

Determination 2 is a determination for the input mode II. In thisexample, the selection condition for determination 2 is that the areaN×1 is greater than the threshold data D21 and that the area N×2 is lessthan the threshold data D22. The threshold data D22 is set to be greaterthan an area of a touched portion, which is obtained when the finger 80lightly touches the display screen 11.

Determination 3 is a determination for the input mode III. In thisexample, the selection condition for determination 3 is that the areaN×1 is greater than the threshold data D21 and that the area N×2 isequal to or greater than the threshold D22. The threshold data D22 isset to be less than an area of a touched portion, which is obtained whenthe finger 80 presses on the display screen 11.

There are different sizes of the finger 80 of the human depending onage, sex, and physical characteristics. In order to cover suchdifferences, a plurality of items of threshold data D21 and D22 may bestored in the storage unit 16 so that a user can select any item of thethreshold data D21 and D22, which is suitable for their finger. Forexample, a large, medium, or small size may be selected. Alternatively,a program for learning the size of the finger 80 of the user may bestored in the storage unit 16.

Accordingly, the input device 100 according to a second embodiment isconfigured such that the controller 15 compares a detected area andbrightness (mainly, the area) of a light-shielded portion formed by anoperating member with a predetermined threshold value to select adesired input mode from among a plurality of input modes.

Therefore, input processing can be implemented for each stage ofoperation (each input mode) according to a pressing state of theoperating member. Furthermore, overall determination based on thedifference-brightness threshold data D11 and D12 and the area thresholddata D21 and D22 ensures more accurate selection.

Third Embodiment

FIG. 11 is a perspective view showing an example structure of a mobilephone 1 according to a third embodiment. The mobile phone 1 shown inFIG. 11 includes an input device 100 according to an embodiment, and isconfigured such that a display screen 11 on which certain inputinformation is displayed is touched. The mobile phone 1 may be anexample of an electronic apparatus, and executes input processing basedon a plurality of input modes in accordance with a pressing state on thedisplay screen 11. The mobile phone 1 implements various types ofinformation processing, such as telephone calling, email communication,or photographing by sliding over the display screen 11 or pressing onthe display screen 11 with the finger 80. In the third embodiment, thesame names and reference numerals as those of the first embodiment havethe same or similar functions and configurations, and will not bediscussed herein.

The mobile phone 1 has a housing 30, and the display screen 11 of theinput device 100 is disposed over substantially the entirety of a frontsurface of the housing 30. In the third embodiment, input informationsuch as a plurality of button icons or an operation panel 8 is displayedon the display screen 11. An icon image for input operation displayed onthe display screen 11 is operated with a finger to enter informationcorresponding to the displayed icon image.

For example, in an address search operation, a list of names of personsstored in a memory is displaced on the displace screen 11. In atelephone number entering operation, the operation panel 8 is displayedon the display screen 11. The operation panel 8 includes a plurality ofpush button switches 2. The push button switches 2 may include, forexample, number keys indicating numbers “0” to “9”, symbol keysindicating symbols such as “*” and “#”, hook buttons such as “on-hook”and “off-hook” keys, and a menu key.

A camera 4 is mounted on a rear surface of the display screen 11, and isoperated to capture an object image. A microphone 3 for telephone callsis mounted in a lower portion on the front surface of the housing 30,and functions as a telephone mouthpiece.

An actuator 20 is provided on an upper center portion on the frontsurface of the housing 30, and has functions of a receiver (or earpiece)for telephone calls and an actuator that provides a tactile sensation.The actuator 20 generates a click sound (cyber-switch operation sound)and gives a tactile sensation to the finger 80 of the operator touchingthe display screen 11 according to the input of information on thedisplay screen 11.

A connector 9 such as a universal serial bus (USB) terminal is placed ona front outer side of the housing 30 to allow communication with anexternal apparatus. A module antenna 6 is mounted inside the housing 30,and a loud sound speaker (not shown) is provided in an inner peripheralportion of the antenna 6 to output sound such as ringer melody or musicattached to video data. A circuit substrate 7 is provided within thehousing 30. A battery 5 is accommodated in the housing 30 to supplypower to the circuit substrate 7, the display screen 11, and otherunits. The mobile phone 1 is configured in the manner described above.

Next, an example internal structure of the mobile phone 1 and a tactilefeedback input method will be described. FIG. 12 is a block diagramshowing an example internal structure of the mobile phone 1.

The mobile phone 1 shown in FIG. 12 is configured such that blockshaving the respective functions are mounted on the circuit substrate 7of the housing 30. The mobile phone 1 includes a controller 15, areceiving unit 21, a transmission unit 22, an antenna duplexer 23, adisplay screen 11, an actuator 20, a power supply unit 33, a camera 4,and a storage unit 16.

A portion of the display screen 11 shown in FIG. 12 is shielded fromlight by a finger 80 of an operator (or user) 81 to produce at leastbrightness information S1 and position information S2. The controller 15includes an analog-to-digital (A/D) driver 31, a central processing unit(CPU) 32, an image processing unit 26, and an actuator driving circuit37. The A/D driver 31 is supplied with the brightness information S1 andthe position information S2 from the display screen 11.

The A/D driver 31 converts an analog signal formed of the brightnessinformation S1 and the position information S2 into digital data toidentify a pressing state of an operating member. The A/D driver 31further performs calculation on the digital data to select an input modeaccording to the pressing state, and supplies flag data D3 foridentifying the input mode, or brightness information D1 or positioninformation D2, to the CPU 32. This calculation may be executed withinthe CPU 32.

The CPU 32 is connected to the A/D driver 31. The CPU 32 controls theoverall operation of the mobile phone 1 according to a system program.The storage unit 16 stores system program data for controlling theoverall operation of the mobile phone 1. A RAM (not shown) is used as awork memory. Upon power on of the mobile phone 1, the CPU 32 reads thesystem program data from the storage unit 16 to load it into the RAM,and boots up the system to control the overall operation of the mobilephone 1.

For example, in response to the input data D1 to D3 from the A/D driver31, the CPU 32 performs control to supply predetermined instruction data[D] to devices such as the batter (power supply unit) 5, the camera 4,the storage unit 16, the actuator driving circuit 37, and a video &audio processing unit 44, to obtain received data from the receivingunit 21, or to transfer transmission data to the transmission unit 22.

The actuator driving circuit 37 is connected to the CPU 32, andgenerates a vibration control signal Sa based on control information Dcfrom the CPU 32. The vibration control signal Sa has a sine outputwaveform. The actuator 20 is connected to the actuator driving circuit37, and is vibrated in response to the vibration control signal Sa.

In addition to the actuator driving circuit 37, the image processingunit 26 is also connected to the CPU 32, and performs image processingon the display information D4 for displaying icons ICx. The displayinformation D4 subjected to the image processing is supplied to thedisplay screen 11.

When the finger 80 receives a vibration, the operator 81 perceives atactile sensation and feels vibration for each function from the CPU 32.Content displayed on the display screen 11 and sound output from theactuator 20 allow the operator to determine the individual functionsthrough visual perception and auditory perception, respectively.

Besides an input screen, a ringer image based on a video signal Sv maybe displayed on the display screen 11.

The antenna 6 shown in FIG. 12 is connected to the antenna duplexer 23,and receives radio wave from the other party at the time of incomingcall from a base station or the like. The antenna duplexer 23 isconnected to the receiving unit 21. The receiving unit 21 receivesreception data directed from the antenna 6 to demodulate audio and videodata, and outputs the demodulated video and audio data Din to the CPU 32or the like. The receiving unit 21 is connected to the video & audioprocessing unit 44 through the CPU 32. The video & audio processing unit44 performs digital-to-analog conversion on digital audio data to outputan audio signal Sout, and performs digital-to-analog conversion ondigital video data to output the video signal Sv.

The video & audio processing unit 44 is connected to the actuator 20having a telephone earpiece function and a speaker function, and a loudsound speaker (not shown). The loud sound speaker outputs sound such asa ringtone or ringer melody at the time of incoming call. The actuator20 receives the audio signal Sout, and increases the volume level of thevoice of the other party. In addition to the actuator 20, the microphone3 serving as a telephone mouthpiece is also connected to the video &audio processing unit 44. The microphone 3 collects the voice of theoperator 81, and outputs an audio signal Sin. At the time of outgoingcall, the video & audio processing unit 44 performs analog-to-digitalconversion on the analog audio signal Sin to be transmitted to the otherparty to output digital audio data, and performs analog-to-digitalconversion on the analog video signal Sv to output digital video data.

In addition to the receiving unit 21, the transmission unit 22 isfurther connected to the CPU 32. The transmission unit 22 modulates datato be transmitted to the other party, such as video and audio data Dout,and to supply the modulated transmission data to the antenna 6 throughthe antenna duplexer 23. The antenna 6 radiates the radio waves suppliedfrom the antenna duplexer 23 to the base station or the like.

In addition to the transmission unit 22, the camera 4 is also connectedto the CPU 32. An image of an object is photographed, and imageinformation such as still-image information or moving-image informationis transmitted to the other party through the transmission unit 22. Thepower supply unit 33 includes the battery 5 (not shown in FIG. 12) tosupply direct-current (DC) power to the controller 15, the displayscreen 11, the receiving unit 21, the transmission unit 22, the actuator20, the camera 4, and the storage unit 16.

Accordingly, the mobile phone 1 provides direct input of positioninformation of an icon touched by an operator, and enables selection ofa desired input mode from among a plurality of input modes according toa pressing state of the operator. Further, in case of using differentapplications, different input modes can be implemented in accordancewith the operations of the different applications.

Furthermore, a detection area, such as the detection areas F3 and F4shown in FIG. 4B, can be defined in an edge portion of the operationpanel 8 of the third embodiment. With the use of such a detection area,a tactile sensation of tracing along the periphery of an existingoperation button can be given to the operator, and an operation similarto the operation of an existing mobile phone can be implemented.

Fourth Embodiment

FIG. 13 is a perspective view showing an example structure of a videocamera 400 according to a fourth embodiment, including an input device100 according to an embodiment. The video camera 400 shown in FIG. 13may be another example of an electronic apparatus, in which a displayscreen of the video camera 400 is touched by an operating member (oroperator) to enter information. The video camera 400 captures an objectimage and records ambient sound. The video camera 400 includes the inputdevice 100, which is described in the first embodiment. A display screen11 and a storage unit 16 according to an embodiment are applied to theinput device 100.

The video camera 400 has a casing 402 that defines an outer surface, anda lens barrel 403 having a photographic optical system 404 incorporatedtherein is provided on an upper portion on a front surface of the casing402. The lens barrel 403 has an image element (not shown) incorporatedat a rear end thereof. The image element is configured to capture anobject image introduced by the photographic optical system 404.

Various operation switches 405 including a power switch, a shootingstart/stop switch, and a zoom switch are provided on a rear surface,upper surface, and side surfaces of the casing 402. A touch paneldisplay device 401 is disposed on a left side surface of the casing 402so as to be connected to the casing 402 in an openable and closablemanner through a hinge 406, and displays an image captured by theimaging element (not shown).

The touch panel display device 401 includes the input device 100 and theactuator 20 having an actuator function, which are described in thefirst embodiment.

In the fourth embodiment, when an icon image for input operationdisplayed on the display screen 11 serving as a monitor of the touchpanel display device 401 is operated with a finger of an operator, adesired input mode is selected according to the brightness or area of alight-shielded portion formed by the finger, and is executed. Further, aclick sound (cyber switch operation sound) is generated from theactuator 20, and a tactile sensation is given to the finger of theoperator touching the display screen.

Accordingly, the video camera 400 according to the fourth embodimentincludes the optical input device 100 according to an embodiment. Thecontroller 15 compares a detected area or brightness of a light-shieldedportion formed by an operating member with a predetermined thresholdvalue to select a desired input mode from among a plurality of inputmodes. Therefore, input processing can be implemented for each stage ofoperation (each input mode) according to a pressing state of theoperating member.

Since the actuator 20 is provided, a tactile sensation can be given to afinger of an operator of the video camera 400 on the basis of an inputoperation on the display screen 11.

Fifth Embodiment

FIG. 14 is a perspective view showing an example structure of a mobilepersonal computer (PC) 500 according to a fifth embodiment, including aninput device 100 according to an embodiment. The mobile PC 500 shown inFIG. 14 may be another example of an electronic apparatus, in which adisplay screen is touched by an operating member (or operator) to enterinformation. The mobile PC 500 performs various kinds of data processingincluding audio and video processing. The mobile PC 500 may also capturean object image and record ambient sound. The mobile PC 500 includes theinput device 100, which is described in the first embodiment. A displayscreen 11 and a storage unit 16 according to an embodiment are appliedto the input device 100.

The mobile PC 500 includes a lower housing 901 that is shaped into atray having left and right hand grips 50 a and 50 b, and an upperhousing 902 slidable over a top surface of the tray. For example, thehousings 901 and 902 are slidably (or rotatably) engaged with each otherby a hinge mechanism 91. The hinge mechanism 91 allows slidableengagement between a sliding section (not shown) disposed at apredetermined position on an operation surface of the lower housing 901and an engagement receiving section (not shown) disposed at an end on aback side of the upper housing 902 so that the upper housing 902 issurface-connected to the lower housing 901 with a sliding degree offreedom corresponding to a predetermined moving distance.

The lower housing 901 has an operation panel 98 provided on an uppersurface thereof. The operation panel 98 includes a plurality of pushbutton switches 92 arranged in a matrix. The push button switches 92 mayinclude “kana” keys indicating Japanese kana characters “a” to “n”, analphabet keys indicating alphabetic characters “A” to “Z”, number keysindicating numbers “0” to “9”, symbol keys indicating symbols such as“*” and “#”, hook buttons such as “on-hook” and “off-hook” keys, and amenu key. A connector 99 such as a USB terminal is placed on a frontouter side of the lower housing 901 to allow communication with anexternal apparatus.

A module antenna 96 is mounted in an inside upper portion of the lowerhousing 901, and a loud sound speaker (not shown) is provided in aninner upper peripheral portion of the antenna 96 to output sound such asringer melody or music attached to video data. In addition to the hingemechanism 91, a circuit substrate 97 is also provided within the lowerhousing 901. A battery 94 is accommodated in the left hand grip 50 a ofthe lower housing 901 to supply power to the circuit substrate 97, thedisplay screen 11, and other units. A microphone 93 for telephone callsis mounted in the right hand grip 50 b, and functions as a telephonemouthpiece.

The upper housing 902 slidably engaged with the lower housing 901 by thehinge mechanism 91 has a display screen 11. A camera 54 is mounted onthe display screen 11, and is operated to capture an object image. Amicro actuator 20 having an actuator function is provided on a surfaceof the upper housing 902, for example, in an upper left portion on thesurface. The micro actuator 20 functions as a receiver (or earpiece) fortelephone calls and an actuator for providing a tactile sensation.

An input device 100 having a tactile sensation function is disposedbelow a surface of the upper housing 902 where the speaker is mounting.The input device 100 has the display screen 11, and selects and executesan input mode from among a plurality of input modes according to apressing operation of an operating member on an input detection surfaceof the display screen 11. On the display screen 11, input informationsuch as a plurality of button icons is displayed. Also in the fifthembodiment, when an icon image for input operation displayed on thedisplay screen 11 is operated with a finger 80, a desired input mode isselected according to the brightness or area of a light-shielded portionformed by the finger 80 and is executed. Furthermore, a click sound(cyber switch operation sound) is generated from the actuator 20, and atactile sensation is given to a finger of an operator touching on thedisplay screen 11.

Accordingly, the mobile PC 500 according to the fifth embodimentincludes the optical input device 100 according to an embodiment. Thecontroller 15 compares a detected area or brightness of a light-shieldedportion formed by an operating member with a predetermined thresholdvalue to select a desired input mode from among a plurality of inputmodes. Therefore, input processing can be implemented for each stage ofoperation (each input mode) according to a pressing state of theoperating member. In this manner, the mobile PC 500 equipped with theoptical input device 100 can be provided.

In the foregoing embodiments, electronic apparatuses have been describedin the context of the mobile phone 1, video camera 400, and mobile PC500 including an optical input device. However, these electronicapparatuses are illustrative, and may include an existing two-axishinged mobile phone, a slide-opening mobile phone, a portable terminalapparatus having upper and lower housings each of which is provided witha display screen, and a digital camera.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present subjectmatter and without diminishing its intended advantages. It is thereforeintended that such changes and modifications be covered by the appendedclaims.

The invention is claimed as follows:
 1. An optical input device having adisplay screen, a portion of the display screen being shielded fromlight by an operating member to implement input processing based on aplurality of input modes, the input device comprising: input detectionmeans including a display unit configured to display predetermined inputinformation, the input detection means detecting at least one of an areaand brightness of a light- shielded portion formed on the display screenby the operating member by approaching the display unit; and controlmeans for providing display control of the display unit and inputcontrol on the basis of the at least one of an area and brightnessdetected by the input detection means, wherein the control meanscompares the detected at least one of an area and brightness with apredetermined threshold value to select a desired input mode from amongthe plurality of input modes, and wherein the control means defines adetection area corresponding to a same piece of input informationdisplayed on the input detection means for each of the plurality ofinput modes, and at least one of a size and a shape of the detectionareas corresponding to the same piece of input information is differentfor each of the input modes, and wherein the same piece of inputinformation displayed on the input detection means is an icon, and thecontrol means defines a first detection area corresponding to andoverlapping the icon in a first input mode as an edge portion of theicon, and defines a second detection area corresponding to andoverlapping the icon in a second input mode as a center portion of theicon, wherein the input detection means displays adjacent icons, each ofthe adjacent icons having an edge portion of a respective icon as adetection area in the first input mode and having a center portion ofthe respective icon as a detection area in the second input mode,wherein a space between detection areas of the adjacent icons is largerin the second input mode than in the first input mode.
 2. The inputdevice according to claim 1, wherein the control means executes inputprocessing in the desired input mode on the basis of at least one of adetected position and movement of the light-shielded portion within thedetection area.
 3. The input device according to claim 1, furthercomprising vibration means connected to the control means, the vibrationmeans vibrating the display screen on the basis of a vibration patterncorresponding to the desired input mode.
 4. A storage medium storing aprogram adapted to implement input processing based on a plurality ofinput modes according to a light-shielding operation performed, using anoperating member, on predetermined input information displayed on adisplay screen, the program comprising the steps of: detecting by aninput detection means at least one of an area and brightness of alight-shielded portion formed on the display screen by the operatingmember by approaching the display screen; comparing the detected atleast one of an area and brightness with a predetermined threshold valueto select a desired input mode from among the plurality of input modes;defining a detection area corresponding to a same piece of inputinformation displayed on the display screen for each of the plurality ofinput modes, and at least one of a size and a shape of the detectionareas corresponding to the same piece of input information is differentfor each of the input modes, wherein the same piece of input informationdisplayed on the display screen is an icon, and a first detection areacorresponding to and overlapping the icon in a first input mode isdefined as an edge portion of the icon, and a second detection areacorresponding to and overlapping the icon in a second input mode isdefined as a center portion of the icon; detecting at least one of aposition and movement of the light-shielded portion within the detectionarea for the desired input mode; and determining input processing in thedesired input mode on the basis of the detected at least one of aposition and movement, wherein an adjacent icons displays by the inputdetection means, each of the adjacent icons having an edge portion of arespective icon as a detection area in the first input mode and having acenter portion of the respective icon as a detection area in the secondinput mode, wherein a space between detection areas of the adjacenticons is larger in the second input mode than in the first input mode.5. An information input method for implementing input processing basedon a plurality of input modes according to a light-shielding operationperformed, using an operating member, on predetermined input informationdisplayed on a display screen, the information input method comprisingthe steps of: detecting by an input detection means at least one of anarea and brightness of a light-shielded portion formed on the displayscreen by the operating member by approaching the display screen;comparing the detected at least one of an area and brightness with apredetermined threshold value to select a desired input mode from amongthe plurality of input modes; defining a detection area corresponding toa same piece of input information displayed on the display screen foreach of the plurality of input modes, and at least one of a size and ashape of the detection areas corresponding to the same piece of inputinformation is different for each of the input modes, wherein the samepiece of input information displayed on the display screen is an icon,and a first detection area corresponding to and overlapping the icon ina first input mode is defined as an edge portion of the icon, and asecond detection area corresponding to and overlapping the icon in asecond input mode is defined as a center portion of the icon; detectingat least one of a position and movement of the light-shielded portionwithin the detection area for the desired input mode; and determininginput processing in the desired input mode on the basis of the detectedat least one of a position and movement, wherein an adjacent iconsdisplays by the input detection means, each of the adjacent icons havingan edge portion of a respective icon as a detection area in the firstinput mode and having a center portion of the respective icon as adetection area in the second input mode, wherein a space betweendetection areas of the adjacent icons is larger in the second input modethan in the first input mode.
 6. The information input method accordingto claim 5, wherein the step of defining a detection area includesdefining a detection area in an edge portion of a portion where theinput information is displayed on the display screen.
 7. The informationinput method according to claim 5, wherein the step of defining adetection area includes defining a detection area in a center portion ofa portion where the input information is displayed on the displayscreen.
 8. An electronic apparatus comprising: an optical input devicehaving a display screen, a portion of the display screen being shieldedfrom light by an operating member to implement input processing based ona plurality of input modes, the input device including input detectionmeans including a display unit configured to display predetermined inputinformation, the input detection means detecting at least one of an areaand brightness of a light- shielded portion formed on the display screenby the operating member by approaching the display unit, and controlmeans for providing display control of the display unit and inputcontrol on the basis of the at least one of an area and brightnessdetected by the input detection means, wherein the control meanscompares the detected at least one of an area and brightness with apredetermined threshold value to select a desired input mode from amongthe plurality of input modes, wherein the control means defines adetection area corresponding to a same piece of input informationdisplayed on the display screen for each of the plurality of inputmodes, and at least one of a size and a shape of the detection areascorresponding to the same piece of input information is different foreach of the input modes, and wherein the same piece of input informationdisplayed on the display screen is an icon, and the control meansdefines a first detection area corresponding to and overlapping the iconin a first input mode as an edge portion of the icon, and defines asecond detection area corresponding to and overlapping the icon in asecond input mode as a center portion of the icon, wherein the inputdetection means displays adjacent icons, each of the adjacent iconshaving an edge portion of a respective icon as a detection area in thefirst input mode and having a center portion of the respective icon as adetection area in the second input mode, wherein a space betweendetection areas of the adjacent icons is larger in the second input modethan in the first input mode.
 9. An optical input device having adisplay screen, a portion of the display screen being shielded fromlight by an operating member to implement input processing based on aplurality of input modes, the input device comprising: an inputdetection unit including a display unit configured to displaypredetermined input information, the input detection unit beingconfigured to detect at least one of an area and brightness of alight-shielded portion formed on the display screen by the operatingmember by approaching the display unit; and a control unit configured toprovide display control of the display unit and input control on thebasis of the at least one of an area and brightness detected by theinput detection unit, wherein the control unit compares the detected atleast one of an area and brightness with a predetermined threshold valueto select a desired input mode from among the plurality of input modes,wherein the control unit defines a detection area corresponding to asame piece of input information displayed on the display screen for eachof the plurality of input modes, and at least one of a size and a shapeof the detection areas corresponding to the same piece of inputinformation is different for each of the input modes, wherein the samepiece of input information displayed on the display screen is an icon,and the control unit defines a first detection area corresponding to andoverlapping the icon in a first input mode as an edge portion of theicon, and defines a second detection area corresponding to andoverlapping the icon in a second input mode as a center portion of theicon, wherein the input detection unit displays adjacent icons, each ofthe adjacent icons having an edge portion of a respective icon as adetection area in the first input mode and having a center portion ofthe respective icon as a detection area in the second input mode,wherein a space between detection areas of the adjacent icons is largerin the second input mode than in the first input mode.
 10. An electronicapparatus comprising: an optical input device having a display screen, aportion of the display screen being shielded from light by an operatingmember to implement input processing based on a plurality of inputmodes, the input device including an input detection unit including adisplay unit configured to display predetermined input information, theinput detection unit being configured to detect at least one of an areaand brightness of a light-shielded portion formed on the display screenby the operating member by approaching the display unit, and a controlunit configured to provide display control of the display unit and inputcontrol on the basis of the at least one of an area and brightnessdetected by the input detection unit, wherein the control unit comparesthe detected at least one of an area and brightness with a predeterminedthreshold value to select a desired input mode from among the pluralityof input modes, wherein the control unit defines a detection areacorresponding to a same piece of input information displayed on thedisplay screen for each of the plurality of input modes, and at leastone of a size and a shape of the detection areas corresponding to thesame piece of input information is different for each of the inputmodes, and wherein the same piece of input information displayed on thedisplay screen is an icon, and the control unit defines a firstdetection area corresponding to and overlapping the icon in a firstinput mode as an edge portion of the icon, and defines a seconddetection area corresponding to and overlapping the icon in a secondinput mode as a center portion of the icon, wherein the input detectionunit displays adjacent icons, each of the adjacent icons having an edgeportion of a respective icon as a detection area in the first input modeand having a center portion of the respective icon as a detection areain the second input mode, wherein a space between detection areas of theadjacent icons is larger in the second input mode than in the firstinput mode.
 11. The input device according to claim 1, wherein at leastone of a shape and a size of a first detection area corresponding to afirst input mode is different than at least one of a shape and a size ofa second detection area corresponding to a second input mode.